Many ways to do this
as mentioned, you need to know your starting point..
get yourself or diy, a racquet balance board..
Lead tape is easy to use
one of my recent experiments that worked better than expected,, was adding weight on handle..
The racquet was foam filled on handle (important for this case), soo I removed buttcap trap door and used 2x 3" wood screws, screwed in one on each channel of the handle, this gave me the HL balance I wanted..
if your racquet does not have a buttcap trap door! or if the handle is not foam filled,, youll need to use other simpler methods! Such as, using lead tape under the racquet grips..
use the search feature on this site,, many entries youll find interesting on this topic..